Slalom ski binding

ABSTRACT

In one version a safety binding (1) for downhill skiing comprises a toe connection means (5, 24) and a heel connection means (6) for co-operation with corresponding parts of a ski boot (3&#39;), in which the toe connection means comprising a rotatable roller (5) having a support web portion (16) and from the said web portion an upwardly diverging conical portion (17), which roller (5) and its shaft (12) are spring biased and movable in the longitudinal direction of the ski (2). The heel connection means (6) comprises an U-formed clamp (26, 27) which is rotatably mounted about a vertical fixed pin (25) of the binding and which is formed with two parallel upright lock clamps (27) having recesses facing the front part of the binding and co-operating with side rollers (33) of the boot. The toe connection means (5, 24) and the heel connection means is fixed to the ski as shown in one version, or movably mounted thereto as shown in version two.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of Ser. No. 189,922 filedJan. 30, 1980 and now abandoned which was based on PCT/SE 7900116 filedin Sweden May 22, 1979 and based in turn on an earlier Swedish patentapplication No. 78/07010-9 filed June 19, 1978. Priority is claimed toall of the above, and to other Swedish applications. Certified copies ofthe latter are to be found in this application file. Certified copies ofthe above enumerated priority documents are to be found in the fileidentified by the U.S. Patent and Trademark Office as Ser. No. 189,922and now abandoned in favor of this application.

The present invention generally relates to ski bindings, and moreparticularly the invention is directed to a type of slalom binding, socalled release binding, which is formed with a toe fastening means and aheel fastening means which co-operate with the slalom boot in such away, that the binding does not cause a release of the boot at normalskiing but oppositely causes a release of a boot from the binding at arelative force between the slalom boot and the binding exceding apredetermined force. It must be possible to obtain a release either whenthe boot is subjected to a strong rotating movement in relation to theslalom binding or when the boot is raised from the binding at the heelfastening means or possibly at the toe fastening means.

Ski bindings of this type are well known in the art and the ski bindingwhich is at present most commonly used comprises two separate parts,viz. a toe connection means and a heel connection means. The heelconnection means is formed so that it may, by a special actuation, befolded up whereas the toe connection means comprises a bracket whichgenerally can be rotated about a vertical shaft but which by anadjustable spring is kept in a predetermined central position. Theslalom boot is clamped into such a binding in that the boot is put downon the binding and the toe cup is moved into a position underneath thebracket at the toe connection means, whereupon the heel connection meansis stepped on so as to clamp the heel portion of the boot to the ski orthe binding.

It has been found that the friction between the boot and the ski atrotation under load often is too high, so that the binding does notrelease sufficiently early, and to eliminate the said disadvantage onanti-friction plate has been mounted just behind the toe bracket at abottom plate which is connected to the toe connection means. In thiscase it is important that the toe cup bracket is adjusted so that theslalom boot is kept pressed on-to the friction plate and so that thesaid pressure is such that the binding really releases if the boot isrotated vigorously in relation to the ski. Pressing downwards toostrongly or the boot may cause the binding to not release and a toolight clamping may cause the binding to release at too low forces. Alsothe heel connection means must press the boot to the binding with suchforce that the binding releases when the boot is raised with an exactlypredetermined force.

Ski binding of this type are disadvantageous in some respects. Both thetoe connection means and the heel connection means must be adjusted verycarefully depending on the weight of the skier, the skill of the skier,the condition of the ski path and many other factors. The adjustmentmust be made very exactly which is both a time consuming and an accuracydemanding job. It is also very important that the boot is completelyclean at the bottom surface both when adjusting the binding and whenskiing, since snow, ice, sand or any other material at the bottomsurface of the boot cause changes of the release values. Further thefriction plate for the toe cup of the boot is worn by time, and thebinding frequently must be readjusted. Sinse the binding is formed withtwo parts there is also a need for great accuracy when mounting thebinding on the ski, and both rough adjustment and fine adjustment of therelease forces must be made after the binding is mounted on the ski.

In order to eliminate some of the above mentioned disadvantages anothertype of ski binding has entered the market which is a so called platebinding in which the toe connection means and the heel connection meansare mounted in a plate which is releasable and which can in turn beclamped to the ski by means of two fastening means, one for the frontpart of the plate and one for the rear part of the plate.

Also in such plate ski bindings the release is made by rotating andlifting forces, and at release the entire unit of boot and plate isreleased whereas on the contrary the fastening means remain on the ski.

Also in this type of ski binding there are two adjustment means for theplate, one for the front part of the plate and one for the rear partthereof. Also in this bindning there is an anti-friction plate providedjust behind the toe connection means mounted on the ski, and also inthis case snow, ice, sand and other impurities may cause a falserotation release. Also in this case the toe connection means and theheel connection means are separated from each other and also in thiscase the adjustment must be made by means of two separate adjustmentscrews. Like in the previously discussed ski binding the tow connectionmeans and the heel connection means move when the ski bows for instanceat a pit or a hump, and there is a serious risk that the binding falselyreleases at pits or humps of the slope.

Another type of ski binding, in which attempts have been made toeliminate further or other disadvantages comprises a plate, which isscrewed to the underside of the boot and which co-operates with two sidepalls which are screw connected to the ski. Also this binding issensitive to snow, ice or impurities under the boot or under the plate,impurities may easily enter the clamp mechanism for the side palls, andthe side palls must for various reasons be very strongly clamped, andtherefore it may be difficult to put on the boot including theattachment plate on the ski binding, especially for children.

Most of the previously known ski bindings also involve the disadvantagethat the boot always must enter the binding with the toe part firstwhereas it may seem natural to many people to clamp the binding with theheel part of the boot being put down first on the ski or the bottomplate. In most of the previous slalom bindings the heel connection meansis provided to clamp the boot at the rearmost part thereof, whereas fororthopedical reasons it is considered more suitable to provide the heelconnection means so as to form substantially an elongation of thelongitudinal direction of the fibula (the lower leg portion). In thiscase a rotation and a subsequent release follows substantially about thecenter of the leg rather than some distance behind the said center likein the previously known ski bindings.

The invention therefore relates to solving the problem to provide asafety ski binding for downhill skiing which

provides a simple connection of the binding to the ski,

provides a simple step-in or treading of the boot into the binding,

is formed as an integral unit of toe connection means, heel connectionmeans and intermediate plate,

provides a good release depending on side forces,

makes a release possible even in the direction upwards of the toeportion,

allows a release upwards for the heel portion of the boot, which has onesingle adjustment means which is common for the entire ski binding,

which keeps the boot safely free from play,

which may easily be moved to other skis,

which is basicly unsensitive to snow, ice, dirt and impurities,

in which the boot can very easily be treated after the binding hasreleased,

which is completely unsensitive to bows of the ski at pits or humpsetc.,

and which is completely maintenance-free.

Thus the invention relates to a safety ski binding for downhill skiingcomprising a toe connection means and a heel connection means forco-operation with corresponding parts of a ski boot, and the inventionis generally characterized in that the toe connection means comprises aconvexly formed support or rotatable roller which is spring biased inthe direction towards the heel connection means and which comprises acylindrical shaft and upwardly diverging conical portion.

In one version of the invention the toe connection means and the heelconnection means are interconnected by means of a binding plate, and theentire binding provides an integral unit which, as a unit, can bemounted directly on the ski. The conical portion of the toe connectionroller may be a biconic roller which in addition to a release both inthe transversal direction and in the direction upwards of the toe partof the boot at super strong load also makes it possible to tread theboot into the binding by pressing the boot straight downwards bycontacting the upper cone of the biconic roller. The heel connectionmeans comprises a pair of clamps having grooves engaging the heelportion of the boot and which co-operate with rollers provided in theboot substantially on line with the fibula of the skier. The heelconnection clamp is preferably rotatably mounted in the intermediateplate and it is suitably formed so that the boot can be mounted also inthat the heel portion of the boot is pressed straightly downwards. In aparticular embodiment of the invention there is an essentialcharacteristics in that the boot does not directly contact the bindingplate but there is a small space between the binding plate and the bootwhat makes the ski binding faily unsensitive to snow, ice and impuritiesat the underside of the boot.

In the presently preferred version of the invention a base plate carriesa toe connection means at one end for a ski boot toe and at the oppositeend a heel connection means for the ski boot heel. The toe connectionmeans comprises a convexly formed support or roller which co-operateswith a concavely formed portion at the toe of the ski boot, and the heelconnection means comprises a rotatably mounted U-formed bracket havingclamp grooves co-operating with side rollers or any other connectionmeans at or adjacent the heel of the ski boot. The toe roller is springbiased in the direction towards the heel connection means and it isformed conical so that the ski boot can be tread down while slidingalong the conical portion of the roller. The roller is formed with aneck which is undercut from the conical portion of the roller and inwhich the concavely formed toe portion of the boot engages in a lockingengagement. The release of the ski binding generally follows by rotatingthe ski boot about the heel connection means so that the concave toeportion is twisted of the toe roller. Release also may follow by astrong actuation upwards at the toe or at the heel.

A ski binding of this type is known from the Swedish patent applicationSer. No. 78 07010-9 filed under Ser. No. 189,922 in the United Statesand having Swedish publication No. 409 176. The said previously knownski binding comprises as mentioned above a base plate on which both atoe connection roller and a heel connection bracket are mounted, and thebase plate together with the toe connection means and the heelconnection means is screwed to a ski at or adjacent the prompt and therear ends respectively of the base plate. By such mounting of the skibinding the ski becomes more or less butt mounted between the connectionpoints of the binding so that the ski can not bow upwards or downwardsrespectively between the said connection points. In some cases this maybe disadvantageous, especially when race skiing whereby it is a wish tohave the ski follow the formations of the hill as carefully as possible.

The object of the invention therefore is the problem to provide a safetyski binding of the above mentioned type which is formed and mounted atthe ski so that the ski may bow upwards or downwards between theconnection points to the binding. According to the invention this objectis fulfilled in that the base plate is fixed mounted at the ski only atone end whereas the opposite end of the binding is mounted at the skiover a connection point which is movable in the longitudinal directionof the ski. Preferably the fixed connection point is provided at theheel portion of a base plate whereas the movable connection point isprovided by a slid which is screwed to the ski in front of the baseplate and which co-operates with a pin projecting from the base plateandd which is slidable and slightly rotatable in a guide of the saidslide means.

By mounting the binding as mentioned above the ski has a possibility ofmoving while bowing upwards or downwards in relation to the base plateof the ski binding between the connection points and it may even rotateslightly in relation to the base plate. As a consequence the ski maysatisfactorily follow the formations of the hill and an improved hillkeeping property of the ski is obtained, there is a reduced tendency ofthe ski to cut through the snow and thereby an increased speed duringskiing may be obtained. The slidable connection at the front end or toeend of the binding, however, gives a displacement forwardly andrearwardly at the front connection point as compared with the abovemenitoned previously known ski binding what from different viewpointsmay be disadvantageous in spite of the fact that such mounting of theski binding is still better than the fixed mounting of the binding aspreviously known. It may also involve certain problems that the skibinding at the front end moves slightly in relation to the ski while theski bows upwards or downwards underneath the ski.

According to a further embodiment of the invention it is thereforesuggested that the ski binding is formed and mounted at the ski so thata displacable connection is obtained at least at or adjacent the rearend of the binding. Thereby the above mentioned problems with thedisplacable front connection means is solved and a very good effect isobtained especially for race ski bindings.

The displacable connection between the binding and the ski mayalternatively be located at some place underneath the base plate betweenthe toe or heel portions thereof while the fixed connection point isprovided at the rear end of the binding. In relation to the abovementioned apparatus having a displacable connection with a forwardlyprojecting pin a still improved ground keeping property is obtained inthat the displacable connection points is located closer to a linecorresponding to the gravity center line of the body of the skier.

It is also possible to provide a displacable connection both at the rearend and at the front end of the binding. It is essential to theinvention that there is at least one dispacable connection between thebinding and the ski and preferably at the said displacable point ofconnection is located a substantial distance rearwardly of the toeportion of the binding and of the ski boot.

Further characteristics and advantageous of the invention will beevident from the following detailed specification in which referencewill be made to the accompanying drawings. It should, however, bepointed out that the described and shown embodiments of the inventionare only illustrative examples which do not restrict the invention andthat many different variations and modifications may be presented withinthe scope of the appended claims.

In the drawings

FIG. 1 diagrammatically and in a perspective view nearly from in frontillustrates a ski binding according to the invention and the belongingboot;

FIG. 2 diagrammatically and in a perspective view from behind shows thesame ski binding but without the boot;

FIG. 3 is a vertical cross section centrally through an embodiment ofthe ski binding and

FIG. 4 illustrates the same ski binding from the above and in partdiagrammatically;

FIG. 1A diagrammatically and in a perspective view shows a safety skibinding of the invention;

FIG. 2A is a top view of the ski binding according to FIG. 1A showingthe essential inner parts thereof with dotted lines;

FIG. 3A is a side view of the ski binding of FIG. 2A showing for thesake of clearness some parts broken;

FIG. 4A is a top view of an alternative embodiment of the inventionhaving a slidable connection at the rear end of the binding, and

FIG. 5A is a partially cut through side view of the ski binding of FIG.4A;

FIG. 6A is a side view of another modified embodiment of the invention,and

FIG. 7A is a partially cut through side view of a still furtherembodiment of the invention.

With reference to FIGS. 1-4 of the drawings there is shown a safety skibinding 1 for downhill skiing which is formed as an integral unit andadapted to be mounted on a ski 2 and for use together with a ski boot 3having special fittings adapted to the binding. The binding generallycomprises a base plate 4 which at its front end carries a toe connectionmeans in a form of a conical or biconical roller 5 and which at the rearend carries a heel connection means 6 for the boot.

As best illustrated in FIG. 3 the base plate 4 is formed as a box whichis at least partly hollow and which comprises a top plate 7 a bottomplate 8 and sides 9. The plates 7 and 8 may be of metal, for instancealuminum, which is suitably treated to act repellant to snow, ice anddirt etc. At the front end the base plate 4 carries the toe connectionmeans 5 for the boot 3 and at the rear end the base plate carries theheel connection means 6 for the boot 3.

The toe connection means includes a slide 10 which is slidable in thelongitudinal direction of the ski binding inside the base plate 4 and itis guided by two longitudinally extending guide bars 11. In the slide 10a pin screw 12 is mounted which extends up through a longitudinal slot13 of the top plate 7. The upper portion of the pin screw 12 carries thetoe connection roller 5 on ball bearings 14 so that the roller by theleast possible friction can rotate about the pin screw 12. The roller 5is formed with a guiding base disc 15 contacting or provided adjacentthe top plate 7, and from the base disc 15 a short web portion extendsupwards which runs into an upwardly diverging cone 17. The cone anglecan be varied according to the circumstances, but a suitable cone anglemay be 45°. From the diverging cone 17 the roller is formed with anupwardly converging second cone 18, so that the roller provides a biconehaving a cone angle tip or narrow border surface 19. The cone surface 17acts to enable a release by rotating the boot 3 upwards from the heelconnection means and the cone surface 18 acts to enable a treading ofthe boot into a binding with the toe moved downwards over the conesurface 18. At the front short end the base plate 24 has a projectingscrew support 20 which is fixed connected to the base plate, and throughthe said screw support a screw 21 extends rearwardly to a shoulder ofthe slide 10. The portion of the screw 20 facing the slide 10 is taperedat 22, and there is a shoulder between a narrow portion 22 and the wideportion of the screw. On the narrow portion 22 of the screw a number ofcup springs 23 are mounted and the said springs are clamped between theshoulder of the screw 21 and the slide 10. By adjusting the screw 21 itis consequently possible to provide a stronger lighter clamp force forthe boot. By further reducing or increasing the number of cup springsthe binding can easily be adapted to different sizes of boots or toboots of different types.

For co-operation with the roller 5 the boot is provided with aconnection bar 24 at the toe cup thereof. The connection bar 24 isscrewed or in any other way stably mounted on the boot and it is bowformed or angularly formed. The angle and the length of the connectionbar 24 is adapted to the intended effect. A short connection bar or aconnection bar having a wide opening angle gives a quicker release thana long connection bar or a bar having a more narrow opening angle. Bythe bow form or angle form the boot gets a possibility to rotate somedistance in relation to the roller 5 while the said roller 5 is pressedforwards against the action of the cup springs 23, and if the torquedoes not exceed the maximum torque for release the spring biassed roller5 presses the boot back to its initial position as soon as the torque orthe rotation force ceases. Since the binding is completely symmetricalthe boot may rotate in both directs with the same effect. At the rearend of the binding the top plate 7 and the bottom plate 8 projects somedistance outside the base plate 4 and between the said projectingportions of the plates 7 and 8 the heel connection means 6 is rotatablymounted about a vertical pin 25. The heel connection means or the heelclamp is formed by a bottom plate 26 which is rotable about the verticalpin 25 and which at each side of the binding carries an upwardlyprojecting lock clamp 27. The lock clamps 27 can be screwed or mountedin any other way at the bottom plate 26 and at the front edges each lockclamp 27 is formed with a recess preferably in the form of threestraight edges of which the bottom edge 28 extends parallelly to thebase plate 4, the rear end 29 upwards at some angle rearwardly from thebottom edge 28 and the upper edge 30 extends forwards-upwards at someangle to the horisontal plane. Above the recesses the lock clampsprovide a forwardly directed ear 31 the front edge 32 of which isdirected upwards-rearwards at some angle to the horisontal plane. Theangles of the upper edge 30 and the front edge 32 are determinedaccording to the circumstances. The purpose of the upper edge 30 is tomake a release possible by lifting the boot upwards with a forceexceeding a predetermined maximum clamp force, and the purpose of thefront edge 32 is to enable a treading of the boot straight downwardsinto the binding.

For co-operation with the lock clamps 27 the boot is provided with aroller 33 on both sides thereof. The roller 33 is formed with a verticalor slightly conical flange 34 and a horizontal cylindrical portion 35.The purpose of the flange 34 is to provide a guiding of the boot intoexact position against the lock clamps 27, and the purpose of thehorisontal cylindric portion 35 is to provide a locking of the boot inthe lock clamps. Therefore the dimension of the horizontal portion 35 ofthe rollers 33 is adapted to the dimensions of the recess 28-30. Itshould be observed that the toe and heel clamps and the correspondingparts of the boot are preferably formed so that the boot is not indirect contact with the top plate 7 but a small space is present betweenthe boot and the top plate to permit a slight amount of snow, ice ordirt on the boot without causing problems.

The binding can be mounted in any suitable way on the ski and in FIG. 3is shown how the binding is mounted by means of screws 36 acting fromunderneath the ski. Preferably the rear portion of the binding isconnected by means of two parallell screws whereas the front portion isconnected by means of one single screw. In order to eliminate the riskof unintentional release in case of pits humps or similar the bindingcan be mounted on a slight distance above the upper surface of the ski,and for this purpose a space washer 37 is provided between the ski andthe binding which permits the ski to bow without inflicting the binding.

In the conventional way the binding can be provided with recesses for acatch strap for instance in the form of a slot 38 provided in theportion of the bottom plate 8 projecting rearwardly or the binding canbe provided with a stop means of a type known per se which releases andstops the ski as soon as the boot is removed upwards from the binding.

The binding according to the invention may as a complete unit bemanufactured and adjusted in a factory together with a boot and there isno need for a complicated mounting or adjusting. The only thing whichpossibly remains is the adjustment of the release force depending onspecial demands from the skier and this is made by one single adjustmentmeans, viz. the screw 21. The boot can very simply be treaded into thebinding either in that the toe connection bar 24 is introduced in thetoe roller 5 whereupon the boot is treaded downwards with the heelportion, whereby the cylinder part 35 of the boot roller 33 slides alongthe front edge 32 of the lock clamp 27 and snaps into the recess 28-30,or in that the boot is mounted in the opposite way, viz. so that theheel portion is firstly moved into the lock clamps 27, whereupon the toeportion of the boot is treaded down over the biconical roller 5. Sincethere is no coonnection between the underside of the boot and thebinding both ways of treading the boot into the binding are easy, and inboth ways the double cone roller is moved somewhat against the action ofthe cup springs 23 until the toe or heel portion of the boot has snappedinto its respective connection means.

The ski binding according to the invention as illustrated in FIGS. 1A-3Agenerally comprises a base plate 1' which carries both a toe connectionmeans 2' and a heel connection means 3' for a ski boot 4'. The baseplate 1' is formed as a box having a substantially even upper surface 5'encasing some vital portions for the actuation of the toe connectionmeans 2'. The base plate may be solid or hollow made of metal, plasticor any other suitable material and having recesses for the inner movableparts. Adjacent the rear end the base plate is formed with a steppeddown portion 6' for mounting of a heel connection means 3'. The uppersurface of the heel connection means extends substantially on level withthe upper surface 5' of the base plate.

The heel connection means 3' is made as a substantially U-formed brackethaving a bottom and from the bottom upwardly projecting side plates 8'formed with an obliquely upwards-forwards directing slot 9' in whichside connection means like side rollers 10' at the heel of the ski boot4' are adapted to engage. The slot 9' has a horizontal bottom edge butan obliquely upwards directed upper edge so that a release may follow inthat the ski boot is pulled upwards from the heel. The heel connectionmeans 3' is mounted freely rotatable about a central pin 11' mounted inthe base plate 1'.

In the embodiment of FIGS. 1A-3A the toe connection means is a rotatableroller 2' having a lower horizontal cylindrical disc 12, from the saiddisc 12' a projecting narrow neck 13' which is widened to an upwardlybevelled cone 14' against which a concavely formed portion 15' of theski boot is adapted to slide while treading the boot into the binding.

The base plate which is preferably made of aluminum, plastic or anyother suitable material has a recess 16' provided from underneath. Therecess provides an encasing frame 17' in which a slide 18' isdisplacably mounted. The toe roller 2' is by a vertical shaft 19'mounted in the slide 18'. The roller is rotatable on the said shaft 19'and extends through an elongated bore 20' in which the shaft 19'together with the roller 2' can be moved from the illustrated rearposition, which is a stop position, to a position spaced to the left asshown in the drawing which position is taken when the ski boot 4' hasbeen tread into the binding.

The frame 17' has a central inner yoke 21' through a clamp screw 22'extends. The clamp screw 22' is threaded into a spring carrier 23' whichon opposite sides of yoke 21' carries a spring pac 24'. The spring 24'preferably is a pac of leaf springs. The spring pacs 24' are kept undertension by a tension wire 25' extending from one spring pack forwardlyand in a U-formation through the slide 18', round the shaft 19' of theroller 2' and back to rear end of the other spring pac. The tension wire25' is over washers 26' fixed mounted at the ends of each spring pac.

By pulling the clamp screw 22' the spring carrier 23' is pulled towardsthe yoke 21' whereby the spring pacs 24' are tensioned. Therebydifferent spring tensions for the toe roller 24 may be obtained givingany intended release force.

Just in front of the stepped down portion 6' of the base plate there isa double-conical formed vertical through slot 27' the rear cone portionof which is preferably lined with a plastic lining, for instance aself-lubricating plastic sleeve 28'. In the slot 27' a brake 29' ismounted. The brake 29' is made as an angularly bent bail of someresilient material providing a two-armed lever which is rotatable abouta shaft extending sideways through the base plate adjacent the rear endof the rear cone portion of the slot 27'. One lever arm provides twobrake arms 31' extending rearwards and/or rearwards-downwards aside ofthe base plate 1' and of the ski 30'. At the outer ends the brake arms31' are formed with brake sleeves 32' of some suitable material likeplastic. From the arms 21' the bail is bent angularly and extendsthrough material of the base plate in which the bail provides pivotshafts 33 for the brake. The other lever arm provides a forwards and/orforwards-upwards directed clamp 34' of a size which may be received inthe front portion of the slot 27'. From the longitudinal center of thebrake the pivot shafts 33' extend outwards-rearwards and in additionthereto slightly downwards thereby providing a spring actuation of thebrake tending to press the brake to the brake position as shown in FIGS.1' and 3'. By making the brake slightly prestressed it tends in thenon-actuated state to rotate in the clock-wise direction as illustratedin FIG. 3A while sliding along the sides of the plastic sleeve 28'. Forfolding the brake in or up it is necessary to press down the clamp 34'whereby the branches of the clamp slide towards the narrowest portion ofthe double conical slot so as to be compressed against the springaction. Such folding of the brake is provided by treading the boot 4'into the binding, whereby the bottom of the boot presses the clamp 34'down and lifts the brake arms 31'.

The base plate 1' with the toe connection means 2', the heel connectionmeans 3' and the brake 29' is mounted slightly spaced above the uppersurface 35' of the ski 30' by means of screws 36' and distance sleevesat the rear end of the binding, for instance at or adjacent the pivotshaft 11' of the heel connection means 3'. At the front end the baseplate is formed with a pin 37' projecting forwardly and having a ballformed head 38' of a suitable radius. The pin 37' is actuallydisplacable and rotatable in a front side 39' which is screwed directlyto the ski 30'. The slide 39' is at the rear end formed a bore 40'having a slide bushing 41' in which the head 38' of the pin is freelydisplacable. The said mounting of the ski binding makes it possible forthe ski 30' to bow both upwards and downwards in relation to the baseplate and also to rotate and to achieve what is of importance, that isto have the ski follow the undulations of the hill as well as possiblewhen down hill skiing, especially when using the binding on easilybendable skiis.

In the embodiment of the invention illustrated in FIGS. 4A and 5A thebinding is fixedly mounted to the ski by means of a screw joint 36'adjacent the front end of the binding. At the rear end the binding isslidably and rotatably mounted in a slide joint 39' which is screwed tothe ski 30' rearwardly of the base plate 1' and which has a bore 40'extending in the longitudinal direction of the ski and which may belined with a friction reducing sleeve. At the rear end of the base plate1' a pin 37' projects which at the end is formed with a substantiallyball formed head 38' which is slidably and rotatably received in thebore 40' of the slide 39'. The ski 30' is free to bow upwards ordownwards underneath the base plate between the front screw joint 36'and the rear slide 39', and the ski also may rotate slightly in relationto the fixed point provided by the front screw joint 36' and the movablepoint provided by the slide connection means 39'.

For some other purposes it may be suitable to have a slidable androtatable connection means located on a line substantially correspondingto the average line of gravity point of the skier. Such line can besupposed to be located somewhere between a vertical line through the toeconnection means 2' and the heel connection means 3'. For suchembodiment the slide connection means should be mounted underneath orpossibly aside of the binding between the toe connection means 2' andthe heel connection means 3'. Such an embodiment is illustrated in FIG.6A, in which a fixed screw joint 36" between the base plate 1' and theski 30' is provided at or adjacent the heel connection means 3', whereasthe binding is mounted by means of a slide 39" at the said average lineof gravity. The pin 37" of the base plate is angularly bent and isslidable and rotatably received in the slide 39". It is obvious that arelative movement between the slide 39" and the pin 37" becomes shorterif the distance between the connection points 36" and 39" is madeshorter and that the operators may be modified accordingly.

For other purposes it may be suitable to mount the binding slidable androtatable as a complete unit on the ski. Such an embodiment isillustrated in FIG. 7A. In this case the binding is mounted with a firstslide 42' at the rear end thereof as shown in FIGS. 4A and 5A, andsomewhere at a forwardly located point the binding is mounted by meansof a second slide 43' of substantially the same type as shown in FIGS.1-3 or FIG. 6. For keeping the binding in the intended position in thelongitudinal direction of the ski 30' a spring 44' of the first slide42' is intended to bias the rear pin 37' forwardly, and correspondinglythe front slide 43' has a spring 45' which biases the front pin 37"rearwardly. Depending on which slide is wanted to give the largestaction the springs 44' and 45' are provided differently strong, butnormally it can be considered most suitable to form the front spring 45'stronger than the rear spring 44' so that the main movement is providedat the rear portion of the binding.

For preventing unintentional rotation of the base plate 1' in relationto the ski 30' slide buttons 46' can be mounted between the base plate1' and the ski 30' someplace between the toe connection means and theheel connection means depending on where a rotation of the binding inrelation to the ski is wanted. It is also possible to provide thebinding so that the main longitudinal displacement of the ski inrelation to the binding is received at the rear end of the binding andthat the rotation is provided forwardly from the rear end by providingthe slide buttons 46' at the rear end of the binding or vice versa.

When using the ski binding according to the invention the ski boot 4'is, with the side connection means 10' thereof, moved into the slots 9'of the side plates 8' whereupon the ski boot with the toe portion istread down while the concave portion 15' thereof slides along the coneportion 14' of the toe connection means and snaps into the neck portion13'. This is possible since the toe connection means 4' is resilientlymounted and moves forwardly while treading the boot into the bindinguntil the concave toe portion 15' of the boot snaps over the cone edgeto the neck 13'.

If desired treading of the boot into the binding also may beaccomplished by firstly putting the toe portion of the boot into the toeconnection means 2 and thereafter treading down the heel of the boot,and in this case the side plates 8 are formed with an entering edge 47as indicated with the dotted lines of FIG. 7.

As mentioned above the ski is capable of moving in the longitudinaldirection and to rotate slightly in relation to the binding whileskiing, whereby the ski in the best possible way may follow theformation of the hill and adapt itself to the skiing style of the skier.

Release of the binding may follow in several different ways, namely bylifting the heel so that the side rollers 10' slide out of the slot 9'or by rotating the toe portion of the boot so as to slidably twist outof the toe roller 2'. In special embodiment of the toe connection meansrelease may also be accomplished by moving the toe portion of the bootstraight upwards. As soon as the binding has released and the boot isremoved from the base plate 1' the brake 29 is automatically rotated toits brake position depending on its own spring actuation so that thebrake arms 31' prevent movement of the ski downhill away from the skier.

It is to be understood that the above described embodiments of theinvention which are illustrated in the drawings are only illuminatingexamples and that all kinds of modifications may be presented in thescope of the appended claims.

What is claimed is:
 1. Safety binding for downhill skiing comprising atoe connection means and a heel connection means for cooperation withcorresponding parts of a ski boot, a base plate (4) adapted forattachment to longitudinally spaced locations of a downhill ski, saidtoe connection means comprising a single biconic roller member (5)having a lower support web portion (16) and from the said web portion anupwardly diverging annular surface portion (17) for engagement by a boottoe, which member (5) is movable in the longitudinal direction of theski, and biasing means urging said member (5) toward said heelconnection means, at least one of said toe and heel connection meansprovided on said base plate.
 2. Safety binding according to claim 1,characterized in that the heel connection means comprises a U-formedclamp (26-27), a fixed pin provided in said plate, said clamp rotatablymounted about said fixed pin (25) of said heel connection means. 3.Safety binding according to claims 1 or 2, characterized in that the toeconnection means and the heel connection means are both mounted to saidbase plate (4), said toe connection means including a vertical pin (12)and a slide (19) supporting said pin, said slide being received in saidplate for said movement longitudinally.
 4. Safety binding according toclaim 1 characterized in that the heel connection means comprises twoparallel and upwardly directed lock clamps (27) having recesses facingthe front part of the binding, to receive laterally outwardly projectingportions (35) adjacent the heel of the ski boot, each of said clamps(27) having an upper edge (30) of the said recess extending at someangle to the horizontal plane in order to enable a release upwards ofthe heel part of boot (3), and in that the lock clamp (27) has anentering edge (32) extending upwards-rearwards from the said upper edge(30) in order to enable a treading down of the ski boot heel into theclamps of the heel connection means.
 5. Safety binding according toclaim 4, characterized in that the boot heel portions that projectlaterally are provided at a point substantially corresponding to a planeextending through the tibia of the skier, said portions defined by aconnection roller (33) on each side of the boot, which rollers coactwith the lock clamps (27) to clamp the boot heel into the heelconnection means.
 6. Safety binding according to claim 1, characterizedin that the biconic roller member (5) has a conical upper surface (18)allowing a treading of the boot into the binding from above and whereinsaid upwardly diverging lower surface (17) also comprises a conicalsurface (17) allowing a release in the direction upwards of the boot. 7.Safety binding according to claim 6, characterized in that a verticalpin (12) rotatably supports said roller, a slide (19) which is slidablein the longitudinal direction of the ski and which carries said pin, andspring biasing means to urge said slide toward said heel connectionmeans.
 8. Safety binding according to claim 7, characterized in that twoparallel guide bars (11) are provided in said base plate to slidablyreceive said slide, and in that the biasing means includes an adjustablescrew (21) which is threaded at the front part of the plate and whichhas a shoulder, and said spring means (23) provided between the shoulderof the screw and the slide (10).
 9. Safety binding according to claim 3,characterized in that the base plate (4) is mounted at a slight distanceabove the ski (2).
 10. Safety binding according to claim 3,characterized in that the toe connection means and the heel connectionmeans are formed so that there is a slight space between the under sideof the boot (3) and the upper side of the plate (4).
 11. A ski bindingfor a ski boot (3) having portions (35) projecting laterally outwardlyadjacent the boot's heel and a concave toe portion (24) said bindingcomprising a longitudinally extending plate (4) adapted to bepermanently attached to a ski (2), toe connection means including amember (5) mounted for limited movement longitudinally of said plate(4), a convexly contoured boot contacting portion (17) of said toeconnection means for engaging the boot's concave toe portion (24), aheel connection means including a U-shaped member (6) having upwardlyprojecting legs (27) with forwardly open recesses (30) for engaging saidski boot projecting portions (35), said U-shaped member (6) pivotallymounted for movement on a vertical axis defined in said plate (4), andmeans (22) biasing said movable member (5) rearwardly in said plate (4)toward said vertical pivot axis of said U-shaped member (6).
 12. Thecombination defined by claim 11 wherein said member (5) comprises aroller, a vertical shaft (12) for rotatably supporting said roller (5),a slide (12) movably mounted in said plate (4) and supporting said shaft(10) to provide the limited longitudinal movement of said member (5).13. The combination defined by claim 11 wherein said member (5) has saidconvexly contoured portion (17) defined by an upwardly diverging conicalportion (17) spaced above the upper surface of said plate (4), and saidmember (5) further including an upwardly converging conical portion (18)above said portion (17).
 14. The combination defined by claim 11 whereinsaid forwardly open recesses (30) are each defined by a forwardlyinclined downwardly facing edge (30) spaced above the upper surface ofsaid plate (4), and said recess further including an upwardly andrearwardly inclined edge (32) above said edge (30).
 15. The combinationdefined by claim 14 wherein said member (5) has convexly contouredportion (17) defined by an upwardly diverging conical portion (17)spaced above the upper surface of said plate (4), and said member (5)further including an upwardly converging conical portion (18) above saidportion (17).